![WRstarBH2close An artist's drawing shows a large black hole pulling gas away from a nearby star. (Image: NASA)](https://webarchive.library.unt.edu/web/20130313145333im_/http://blogs.voanews.com/science-world/files/2012/12/WRstarBH2close-300x199.jpg)
An artist’s drawing shows a large black hole pulling gas away from a nearby star. (NASA)
Of all the celestial objects that make up the Universe, nothing is more mysterious than the black hole.
Now Denmark scientists have come up with what they say are groundbreaking theories that explain several properties of the enigmatic black hole. The scientists’ research indicates black holes have properties similar to the dynamics of both solids and liquids.
![Einstein_1921_portrait2 Albert Einstein (circa 1921) theorized that the universe expands, but such expansion slows over time. Recent observations indicate that the opposite may be true that the universe if expanding at an faster rate. (Photo: Creative Commons/Wikipedia)](https://webarchive.library.unt.edu/web/20130313145333im_/http://blogs.voanews.com/science-world/files/2011/09/Einstein_1921_portrait2-240x300.jpg)
Albert Einstein- circa 1921 (Photo: Creative Commons/Wikipedia)
What’s generally known about black holes is that they’re extremely compact –some are as small as less than .01 mm– and that they can generate a gravitational pull so powerful that anything and everything that comes near them is swallowed up, including light.
We’re not able to see these cosmic vacuum cleaners because any light that does hit them is absorbed rather than being reflected. Black holes were predicted by Einstein’s general theory of relativity but scientists haven’t been able to determine their properties.
“Black holes are not completely black, because we know that they emit radiation and there are indications that the radiation is thermal, i.e. it has a temperature,” explains Niels Obers, a professor at the University of Copenhagen.
Obers says one can view black holes like particles. Since, in principle, a particle has no dimensions, it is merely a point. But, if a particle is given an extra dimension –such as a straight line– it then becomes a string. And if you give the string yet an additional dimension, it becomes a plane. Physicists refer to one of these planes as a ‘brane’, similar to the biological term, ‘membrane’.
“In string theory, you can have different branes, including planes that behave like black holes, which we call black branes,” Obers says. “The black branes are thermal, that is to say, they have a temperature and are dynamical objects. When black branes are folded into multiple dimensions, they form a ‘blackfold’.”
![50825_web In theoretical physics you can have different planes that behave like black holes and they are called black branes. When black branes are folded into multiple dimensions they form a 'blackfold', which new research shows has a relationship between gravity and fluid mechanics and solid-state physics. (Artist impression by Merete Rasmussen)](https://webarchive.library.unt.edu/web/20130313145333im_/http://blogs.voanews.com/science-world/files/2012/12/50825_web-300x211.jpg)
Artist impression of black branes forming a “blackfold”(Artist impression by Merete Rasmussen)
Obers and his colleagues say they’ve been able to develop their new theories on the physics of black holes based on the principals of these black branes and blackfolds.
“The black branes are hydro-dynamic objects, that is to say that they have the properties of a liquid,” says Jay Armas, who also worked on the project. “We have now discovered that black branes also have properties which can be explained in terms of solids. They can behave like elastic material when we bend them.”
“With these new theories, we expect to be able to explain other black hole phenomena, and we expect to be able to better understand the physical properties of neutron stars,” said Obers.